Devices for spraying pesticides such as fungicides, herbicides, and insecticides are widely used by farmers throughout the world. Existing sprayers typically are tractormounted implements having a single tank supplying a mixture of pesticide and water to a series of spray nozzles. A pump connected to the tank forces the pesticidal solution from the tank to the nozzles, from which the solution is sprayed onto crops or other vegetation to be protected.
Because existing sprayers utilize but one tank and pesticide is most readily available in concentrated form, the operator must mix undiluted pesticide with water when preparing for a spraying operation. Such manual mixing is relatively imprecise, often precluding the optimal pesticidal solution from being used to spray the crops. Moreover, because existing pump sprayers are relatively inefficient, a portion of the pesticidal solution remains at the end of each spraying and must be emptied by the operator if a solution of different strength or type is needed thereafter. Both mixing and disposal, therefore, pose various dangers to the operator and to the environment, in that the operator is exposed to health risks associated with the handling of pesticides while the residue disposal area is subjected to receiving the pesticidal pollutant.